1. Field of the Invention
The present invention relates to a see-saw button device used in electronic equipment, e.g., a pager, a cellular phone, a scroll button, or an individual radio selective calling receiver.
2. Description of the Prior Art
Conventionally, see-saw button devices for electronic equipment are disclosed in, e.g., Japanese Unexamined Patent Publication No. 1-173526, Japanese Unexamined Utility Model Publications Nos. 64-02331 and 63-184530, Japanese Unexamined Patent Publication No. 62-147233, Japanese Unexamined Utility Model Publication No. 62-98124, Japanese Unexamined Patent Publication Nos. 4-179014, 4-169019, and 63-254629, and Japanese Unexamined Utility Model Publication No. 4-29139.
FIGS. 1A and 1B are perspective views of a conventional see-saw switch described in Japanese Utility Model Publication No. 4-29139 before assembly, in which FIG. 1A shows a button, and FIG. 1B shows a housing into which the button is to be pressed.
The see-saw switch shown in FIGS. 1A and 1B is constituted by a housing 21, a button 22, and press members 30. A semicircular projection 24 and bendable pawls 25 are formed on the bottom surface of the housing 21. The button 22 is constituted by notches 28 for receiving the pawls 25, and guides 29 integrally formed with the notches 28 and having steps. The button 22 is pressed into the housing 21 and is mounted on it by bending the pawls 25. The press members 30 press switches 23 under the button 22. The conventional see-saw button device having the above arrangement has problems as follows.
(1) The switches are juxtaposed and the switch operating portions are located immediately below button press ribs. At least a distance for the operating portions of the switches is required. Therefore, the button becomes inevitably large. In other words, the button press surface becomes large.
(2) Since the switches are arranged between the board and the button and housing, at least a space corresponding to the thickness of the switches must be reserved between the board and the button and housing. Namely, the thickness of the device increases.
(3) Since the operating portions of the switches are located immediately below the button press surface, the button press surface may be undesirably pressed at two portions simultaneously to turn on both the right and left switches undesirably.